Rotary engine



l. D. CARROLL.

ROTARY ENGINE.

APPLICATION FILED MAR.2Z, 19x9.

2 SHEETS-SHEET l.

J. D. CARROLL.

ROTARY ENGINE.

Patented Jan. 11, 1921'.

HEETS-SHEET 2 Lfohnfl TF'OZZ 1?? rm UNITED STA'lEi PATENT OFFICE.

JOHN D. CARROLL, 01" WEST LAFAYETTE, INDIANA, ASSIGNOR T0 TURBO ROTARYENGINE COMPANY, or EVANSVILLE, INDIANA, A CORPORATION or SOUTH DA- KOTA.

ing at West Lafayette, in the county of Tips pecanoe and State ofIndiana, have invented certain new and useful Improvements 111 RotaryEngines, of which the following is p a specification. v

This invention relates to rotary engines, and has reference moreparticularly to improvements in the cylinders of such engines.

In engines of this class, wherein the circular inner wall of thecylinder is traversed by the free edges of-piston vanes or blades, ithas heretofore been proposed to employ oblique steam supply and exhaustports for the purpose of preventing excessive wear on the packingscarried by the outer edges of i the vanes or blades which sweep over theports. By giving to the port an oblique or inclined direction relativelyto the longitudinal direction of the packing strip, a square impact ofthe packing strip on the edge of the port is avoided.

Where, as heretofore, the oblique port is made to extend the full widthof the cylinder wall, one objection arises, growing out of the fact thatthe frictional tendency of the grid bars which space the ports is tocrowd the packing strip always toward one edge of the piston blade,increasing the liability of leakage.

The purpose or object of my present improvement is to provide aconstruction which shall preserve the advantages of the oblique ports,both on the intake side of the engine and on the exhaust and compressionrelief side, and at the same time shall avoid the tendency referred toto continually crowd the packing strip on the end of the piston bladetoward one side of the latter.

My invention, its structural features, and its advantages will all bereadily understood and appreciated by those skilled in the art from thefollowing description, taken in connection with the accompanyingdrawings, in which- Figure 1 is a transverse section through a rotaryengine of the eccentric piston type showing my improvements embodiedtherein;

Fig. 2 is a vertical section on the line 2-2 of Fig. 1;

Fig. 3 is a plane view of the exhaust and ROTARY ENGINE.

Specification of Letters Patent. Pate t d J 1 1921 Application filedMarch 22, 1919. 2

Serial No. 284,401.

COIlPIGSSlOD relief side of the cylinder wall; an Fig. 4' is a viewsimilar to Fig. 3, showing the steam intake side of the cylinder wall,substantially on the line 4-4 of Fig. 1.

Referring to the drawings, 5 designates as an entirety the stationarycylindrical wall of the engine, 6 designates the drivenshaft, 7 desgnates a stationary bearing boss for the piston vanes, which iseccentric to the driven shaft 6, 8 designates a bushing surround ng theboss 7, 9 designates each of a plurality of piston vanes that arejournaled on the bushing 8, and 10 designates a rotary drum structurecarrying rockers 11 in and through which the piston vanes 9 extend withboth a sliding and rocking motion. In the outer ends of the piston vanes9 are mounted packing strips 12, which form steam-tight joints with theinner wall of the cylinder 5.

The parts thus far described are wellknown cooperating elements of acommon type of rotary engine.

Referring now to those structural fea tures wherein my presentimprovements reside, 13 designates as an entirety the steam intake portof the engine, and 14 designates as an entirety the steam exhaust andcompression relief port. Referring to Fig. 4 it will be seen that theintake port 13 is made up of a grid-like structure comprising two seriesof oppositely inclined oblique ports or passageways 15 and 16 that arespaced by a central bar 17 and oblique bars 18 and 19 that separate andspace the individual ports 15 and 16 respectively.

The same structural feature is preserved in the relatively long exhaustand compression relief port 14, this being a grid-like structure of acentral longitudinal bar or strip 20 and oppositely inclined obliqueradiating bars or strips 21 and 22, between which are formed theoppositely inclined oblique individual ports 23 and 24. The direction oftravel of the vane packing 12 over the ports 13 and 14 is indicated byarrows in Figs. 3 and 4.

It will also be observed best by reference to Fig. 3 that the individualports 23 and 24 on the exhaust and compression relief side are ofgradually decreasing width from the lower to the upper end of the port.This construction is preferable for the reason that at the lower end,where the exhaust begins, the exhaust pressure is highest and graduallydecreases toward the upper end. The compression on the advance side ofthe piston vane also decreases toward the upper end of the port. Hence,the total area of the individual exhaust and relief ports is graduatedin accordance with the requirements of the pressures handled on bothsides of the piston vane as the latter is traveling over the port.

It will further benoted, as constituting the principal advantage of thedescribed construction, that the friction effect of the grid-bars on theopposite sides of the central longitudinal bar is to move the packing 12equally toward both sides of the piston vane. The friction effect on oneside, therefore, exactly neutralizes the friction effect on the oppositeside, the result being that there is no tendency LO shift the packingstrip toward either side of the piston vane.

I claim:

1. A rotary engine cylinder having formed structure for the passage ofmotive fluid, comprising a central longitudinal bar and lateral barsextending obliquely from the sides of said central bar in a forwardlyinclined direction relatively to the direction of piston travel andforming between them individual ports.

3. A rotary engine cylinder having formed in the circumferential wallthereof a grid structure for the outlet of motive fluid, comprising acentral longitudinal bar and lateral bars extending obliquely from thesides of said central bar, said lateral bars on each side of saidcentral bar being progressively spaced closer togetherfrom one end tothe other of said grid structure, thereby forming between themindividual ports of progressively decreasing width.

4. A rotary engine cylinder having formed in the circumferential wallthereof a grid structure'for the outlet of motive fluid, com prising a.central longitudinal bar and lateral bars extending obliquely from thesides of said central bar in a forwardly inclined direction relativelytothe direction of piston travel, said lateral bars on each side ofsaidcentral bar being progressively spaced closer together from thepiston-entering to the piston-leaving end of-said grid structure,thereby forming between them individual ports of progressivelydecreasing width.

JOHN D. CARROLL.

